Improvement in india-rubber billiard-cushions



UNITED STATES PATENT OFFICE.

CHARLES L. RionRDs, oE NEW YORK, N. Y.

Specification forming part of Letters Patent No. 10|,l63, dated March z2, 1h70.

To @ZZ whom, it may concern.-

Be it known that I, CHARLEs LLOYD Rion- ARDs, of New York, in thecounty and State of New York, have invented certain new and useful Improvements in Vulcanized India- Rubber Billiard Cushions; and I hereby declare the following to be a full, clear, and exact description ofthe same, reference being had to the accompanying drawing, which represents in perspective a portion of a billiardcushion made in accordance with my invention.

After the introduction of vulcanized rubber as a cushion for billiard-tables, it was found that although the cushion possessed one essential qualiiication-elasticity-its use was attended with a drawback, which counterbalanced to a great extent the advantage derived. The drawback was the inaccuracy of the cushion, or its failure to deflect the ball at an angle equal to the angle of incidence, and this was attributed to the partial embedding` of the ball, when it struck against the cushion, in the elastic and yielding rubber, from which it would naturally, be thrown at a sharper or more acute angle than that 'at which it struck. The object therefore of billiard-table manufacturers was to reduce the yielding properties of the cushion, and this they rst attempted to accomplish by the use of leather, pasteboard, cloth, or a mixture of rubber with brous material applied to the face of the cushion; but

while these devices gave the cushion increased powers of resistance to the ball, they at the A same time deadened it and detracted from its elasticity. The attempt was then made to preserve at the same time the resistant power and the elasticity lof the cushion, as it was found that a cushion which, though resistant, had a reduced elasticity was as defective as one which, although highly elastic, was too soft and yielding. To this end rubber layers of various degrees of hardness were combined in the cushion, and a steel facing was also employed, as well as steel strips, or strips of cloth Y embedded in the cushion and cords stretched along its edge; but all these methods have been found to be defective, for the reason that the elasticity ofthe cushion is more or less impaired, while its accuracy is not essentially increased.

From careful and long-continued experiment I am satisfied that the true remedy for the difficulty above stated has never been ascertained. The efforts in this direction have hitherto resulted in presenting a resistant surface at the point where the ball strikes, and the effect of the impact upon other portions of the cushion, even if noticed, has not been sufficiently guarded against. The ball comes in contact with the upper part or edge only of the slanting face of the cushion, and the comparative size of the ball and cushion is such that if the ball be divided into two equal parts by a horizontal plane, its lower hemisphere will be below the top of the cushion, so that the contact of the cushion is mainly, if not altogether, with the upper half of the ball. The tendency of this is to keep the ball from hopping or jumping from the table; but its further tendency is to cause the ball, when it strikes the cushion, not only to directly indent, but also to force upward, the elastic and yielding material, and this I consider to be the main cause of inaccuracy in the angle of rebound. My object therefore is, while maintaining the elasticity of the cushion virtually unimpaired, to so bind together the face and top and bottom of the cushion as to prevent it from yielding in an upward direction under thel impact of the ball. This I accomplish by the use of a loose open woven fabricsuch as shown at a in the drawing-which is applied to the face of the rubber cushion b while the same is yet in a green or plastic state, the fabric extending over the top edge of the cushion and under the bottom edge, so as to tightly confine the rubber. The latter penetrates the meshes of the fabric, which may also be covered with a thin facing or coating of rubber, and the whole is then vulcanized in the usual way. The cords or threads of the fabric which run from the top to the bottom ofthe rubber effectually prevent the latter from being unduly stretched or forced upward by the ball, and

thelongitudinal threads or cords give sufficient resistant capacity in that direction. The cushion being thus bound, it becomes absolutely inextensible in either direction, while its elasticity under the direct impact of the ball remains unimpaired. It may be thus made to possess any desired degree of elasticity, while continued and careful experiment has demonstrated that the inaccuracy heretofore existing in the cushion is,.for all practical purposes,

l entirely removed. The cushion is thus composed of rubber provided with a facing of loosely-woven reticulated fabric, into the meshes of which the rubber enters, so that the two form one and the same piece. The manner inwhich the body of the cushion is constructed may be varied, (for to that my invention has no relation,) and the netting may be united with the rubber by various means, though I much prefer to put the two together and then unite them by vulcanization. The layer of rubber over the fabric may be more or less thick; or it may be dispensed with, if desired. Vith regard to the fabric used, I

prefer that shown in the drawing, which is manufactured for this express purpose, and is composed of twisted cords or threads resembling ordinary cotton twine; but any suitable netting of an analogous nature may be employed.

tially such as herein described, applied to the face and extended over upon the top 'and bottom of the rubber, and united with the same by vulcaniz'ation or otherwise, as and for the purposes set forth.

In testimony whereof I have signed my name to this specification 4before two subscribing witnesses.

oHAs. L. RICHARDS.

Witnesses:

A. PoLLoK, JOHN L. COBB. 

